diff options
| -rw-r--r-- | net/ipv6/ip6_output.c | 29 |
1 files changed, 18 insertions, 11 deletions
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c index 61741676b987..d5f7716662db 100644 --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -564,18 +564,17 @@ int ip6_fragment(struct sock *sk, struct sk_buff *skb, /* We must not fragment if the socket is set to force MTU discovery * or if the skb it not generated by a local socket. */ - if (unlikely(!skb->ignore_df && skb->len > mtu) || - (IP6CB(skb)->frag_max_size && - IP6CB(skb)->frag_max_size > mtu)) { - if (skb->sk && dst_allfrag(skb_dst(skb))) - sk_nocaps_add(skb->sk, NETIF_F_GSO_MASK); + if (unlikely(!skb->ignore_df && skb->len > mtu)) + goto fail_toobig; - skb->dev = skb_dst(skb)->dev; - icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); - IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), - IPSTATS_MIB_FRAGFAILS); - kfree_skb(skb); - return -EMSGSIZE; + if (IP6CB(skb)->frag_max_size) { + if (IP6CB(skb)->frag_max_size > mtu) + goto fail_toobig; + + /* don't send fragments larger than what we received */ + mtu = IP6CB(skb)->frag_max_size; + if (mtu < IPV6_MIN_MTU) + mtu = IPV6_MIN_MTU; } if (np && np->frag_size < mtu) { @@ -813,6 +812,14 @@ slow_path: consume_skb(skb); return err; +fail_toobig: + if (skb->sk && dst_allfrag(skb_dst(skb))) + sk_nocaps_add(skb->sk, NETIF_F_GSO_MASK); + + skb->dev = skb_dst(skb)->dev; + icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); + err = -EMSGSIZE; + fail: IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_FRAGFAILS); |